Many factors can contribute to resting comfort and overall sleep quality. In terms of sleep satisfaction, sleep positions appear to be related to the quality of sleep one receives. On average, poor sleepers spend more time on their back with their head straight whereas good sleepers occupy more periods of immobility on their sides, commonly referred to as the semi-fetal position. The sleep position of these poor sleepers also appears to correspond with the normal position of sleepers who complain of respiratory problems. Sound sleepers spend more sleep time immobile than poor sleepers while poor sleepers tend to have more movement patterns which seem to disrupt their sleep.
It has been observed that sound sleep is characterized by eight to twelve postural shifts per night, eight hour period, that occur in harmony with the cycles of sleep. These shifts commonly coincide with brief moments of consciousness which, while detectable, go unnoticed by the subject. It is believed that this postural shifting during sleep naturally occurs to stimulate blood flow which works to avoid muscle tension. For these reasons it is believed that some minimal number of postural shifts cannot be avoided.
In contrast, research has shown that some poor sleepers may undergo well over a hundred postural shifts in a typical eight hour sleep period. It is believed that these excessive movements are in response to physical stresses on the body commonly referred to as pressure points. A pressure point occurs when an exceptional amount of pressure is applied for an extended period on a nerve or blood vessel resulting in numbness or pain. In response, the body adjusts to alleviate the pressure. Accordingly, it has been concluded that the quality of sleep is directly related to the comfort level one is able to achieve.
For the average individual, the ability to achieve comfort in a preferred sleeping position is a major step toward improving sleep quality. There have been numerous attempts to design pillows to aid in sleeping comfort as evidenced by the following patents, U.S. Pat. Nos. 3,327,330, 4,060,863, 4,173,048, 4,574,412, 4,754,510 and 4,794,657.
U.S. Pat. No. 3,327,330 relates to an L-shaped pillow with a central body having two wing members that are joined on either side of the body by a transverse seam. The transverse seam acts as a hinge enabling the wings to be folded under the central body. Similarly, U.S. Pat. No. 4,060,863 relates to a substantially V-shaped pillow tapered so that the body presents a substantially flat surface from top to bottom when the arms are folded in contact with each other. Another patent, U.S. Pat. No. 4,731,890 designed to aid mother's during breast feeding, describes a V-shaped pillow having one arm of the perpendicular V-shape wider than the other.
U.S. Pat. No. 4,173,048 relates to a body length pillow with a linear head supporting central portion having two body length extensions extending perpendicularly from the ends of the central portion. U.S. Pat. No. 4,574,412 relates to a L-shaped pillow having a linear head supporting portion with a linear leg portion extending perpendicularly therefrom.
U.S. Pat. No. 4,754,510 relates to a pillow having a pair of generally oval or elliptical shaped portions attached perpendicularly to each other. U.S. Pat. No. 4,794,657 relates to a pillow assembly having a trunk with a head and leg pillow which may be removably attached in different rotational orientations to the trunk pillow.
All these pillows heretofore comprise a combination of linear members extending either linearly or essentially perpendicularly from each other. These linear designs do not approximate the rotational movements of the user's head and/or limbs. Therefore, they do not offer a support range for the rotational movements of the user's head and/or limbs without requiring an active effort on the part of the user to move, typically pull, the pillow into conformity with a particular position of the body. Of course, these pillows need to be repositioned to conform to other body positions. This repositioning or distortion of the pillow from its natural shape causes a stress in the pillow which may result in a counter force on the body, as the pillow attempts to return to a more natural shape. This need to reposition the pillow and the resulting stress combine to inhibit the user from achieving the prolonged comfort necessary for virtually uninterrupted sleep.
For any and all the reasons noted above plus other reasons not discussed herein, it will be appreciated that there is a need for a pillow that is designed to encircle portions of the body and to support the head and/or limbs through a portion of their rotational movements without having to be reconfigured or repositioned.
It therefore an object of this invention to provide a pillow having a shape designed to partially encircle a shoulder of a user resting on their side and support the user's head through substantially the full range of motion of their head with respect to their shoulders.
It is another object of this invention to provide a pillow having a shape designed to partially encircle the neck of a user resting on their back and support the user's head through substantially the full range of motion of their head with respect to their shoulders.
It is still another object of this invention to provide a pillow having a shape designed to partially encircle a shoulder of a user resting on their side and provide a support range that corresponds to the motion of the user's head with respect to their shoulders and a support range for the unsupported arm of the user.
It is yet another object of this invention to provide a full body pillow having a shape designed to partially encircle a portion of the upper body of the user and offer a support range that corresponds to the motion of the user's head with respect to their shoulders while also offering a support range for one or both legs of the user.
It is a further object of this invention to provide a full body pillow designed to offer a support range for the head, arms and legs of the user having a linear portion with a curved portion extending from each end.
It is still a further object of this invention to provide a pillow designed to offer a support range for the head of the user, without having to reposition or reconfigure the pillow, having a substantially fixed radius arc shape.